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The Yanqiang Ling fragmented ophiolite (YLFO) crops out within the southern part of the Duolong ore concentration area, ∼20–30 km to the north of the western Bangong Co–Nujiang suture zone in central Tibet. It was tectonically emplaced within a Late Triassic–Jurassic accretionary complex and can be divided into two groups, western and eastern. Both groups consist of sheeted dikes, basalts, and ribbon cherts, and tectonites developed at the contact between the accretionary complex and tectonic lenses. U-Pb dating of zircons separated from the sheeted dikes and basalts suggests that both the eastern and western parts of the YLFO were generated at or after ∼118 Ma. The mafic sheeted dikes and lavas from both parts display normal mid-ocean ridge basalt–like chondrite-normalized rare earth element patterns and show positive Th and negative Nb anomalies on primitive-mantle-normalized multielement variation diagrams. Detailed geochemical analyses indicate that they were derived from partial melting of upwelling asthenospheric mantle, and the geochemical difference between the two parts might be caused by different degrees of partial melting or variations in their source compositions. Geochemical and geochronological evidence of the YLFO and its geological background suggest that it may represent a small rift within the forearc region due to spreading ridge–trench interaction within the Bangong Co–Nujiang Ocean, which also can explain formation of the Early Cretaceous magmatism and Cu-Au deposits within the Duolong ore concentration area. Our new data also support that the Bangong Co–Nujiang Ocean remained open during the Early Cretaceous, as suggested by earlier workers. [ABSTRACT FROM AUTHOR]